move ks to constcache

Author: oscardssmith

lib/OrdinaryDiffEqRosenbrock/src/rosenbrock_caches.jl

@@ -697,14 +697,15 @@ end
 
 ### Rodas4 methods
 
-struct Rodas4ConstantCache{TF, UF, Tab, JType, WType, F, AD} <: RosenbrockConstantCache
+struct Rodas4ConstantCache{TF, UF, Tab, JType, WType, F, AD, rateType} <: RosenbrockConstantCache
     tf::TF
     uf::UF
     tab::Tab
     J::JType
     W::WType
     linsolve::F
     autodiff::AD
+    ks::Vector{rateType}
 end
 
 tabtype(::Rodas4) = Rodas4Tableau
@@ -721,10 +722,11 @@ function alg_cache(alg::Union{Rodas4, Rodas42, Rodas4P, Rodas4P2}, u, rate_proto
     J, W = build_J_W(alg, u, uprev, p, t, dt, f, uEltypeNoUnits, Val(false))
     linprob = nothing #LinearProblem(W,copy(u); u0=copy(u))
     linsolve = nothing #init(linprob,alg.linsolve,alias_A=true,alias_b=true)
+    ks = Vector{typeof(rate_prototype)}(undef, 6)
     Rodas4ConstantCache(tf, uf,
         tabtype(alg)(constvalue(uBottomEltypeNoUnits),
             constvalue(tTypeNoUnits)), J, W, linsolve,
-        alg_autodiff(alg))
+        alg_autodiff(alg), ks)
 end
 
 function alg_cache(alg::Union{Rodas4, Rodas42, Rodas4P, Rodas4P2}, u, rate_prototype, ::Type{uEltypeNoUnits},

lib/OrdinaryDiffEqRosenbrock/src/rosenbrock_perform_step.jl

@@ -1208,7 +1208,7 @@ end
 
 @muladd function perform_step!(integrator, cache::Rodas4ConstantCache, repeat_step = false)
     (;t, dt, uprev, u, f, p) = integrator
-    (;tf, uf) = cache
+    (;tf, uf, ks) = cache
     (;A, C, gamma, c, d, H) = cache.tab
 
     # Precalculations
@@ -1230,7 +1230,6 @@ end
 
     # Initialize k arrays
     num_stages = size(A,1)
-    ks = Vector{typeof(u)}(undef, num_stages)
 
     # Loop for stages
     for stage in 1:num_stages

lib/OrdinaryDiffEqRosenbrock/src/stiff_addsteps.jl

@@ -291,7 +291,7 @@ function _ode_addsteps!(k, t, uprev, u, dt, f, p, cache::Rodas4ConstantCache,
         always_calc_begin = false, allow_calc_end = true,
         force_calc_end = false)
     if length(k) < 2 || always_calc_begin
-        (;tf, uf, du) = cache
+        (;tf, uf, ks) = cache
         (;A, C, gamma, c, d, H) = cache.tab
 
         # Precalculations
@@ -319,7 +319,6 @@ function _ode_addsteps!(k, t, uprev, u, dt, f, p, cache::Rodas4ConstantCache,
         end
 
         num_stages = size(A, 1)
-        k = Vector{typeof(du)}(undef, num_stages)
 
         for stage in 1:num_stages
             u = uprev